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Error from SQL query

Currently I'm working on cleaning up some code on the backend of an application I'm contracted for maintenance to. I ran across a method where a call is being made to the DB via Oracle Data Reader. After examining the SQL, I realized it was not necessary to make the call to open up Oracle Data Reader seeing how the object being loaded up was already within the Context of our Entity Framework. I changed the code to follow use of the Entity Model instead. Below are the changes I made.
Original code
var POCs = new List<TBLPOC>();
Context.Database.Connection.Open();
var cmd = (OracleCommand)Context.Database.Connection.CreateCommand();
OracleDataReader reader;
var SQL = string.Empty;
if (IsAssociate == 0)
SQL = #"SELECT tblPOC.cntPOC,INITCAP(strLastName),INITCAP(strFirstName)
FROM tblPOC,tblParcelToPOC
WHERE tblParcelToPOC.cntPOC = tblPOC.cntPOC AND
tblParcelToPOC.cntAsOf = 0 AND
tblParcelToPOC.cntParcel = " + cntParcel + " ORDER BY INITCAP(strLastName)";
else
SQL = #"SELECT cntPOC,INITCAP(strLastName),INITCAP(strFirstName)
FROM tblPOC
WHERE tblPOC.cntPOC NOT IN ( SELECT cntPOC
FROM tblParcelToPOC
WHERE cntParcel = " + cntParcel + #"
AND cntAsOf = 0 )
AND tblPOC.ysnActive = 1 ORDER BY INITCAP(strLastName)";
cmd.CommandText = SQL;
cmd.CommandType = CommandType.Text;
using (reader = cmd.ExecuteReader())
{
while (reader.Read())
{
POCs.Add(new TBLPOC { CNTPOC = (decimal)reader[0],
STRLASTNAME = reader[1].ToString(),
STRFIRSTNAME = reader[2].ToString() });
}
}
Context.Database.Connection.Close();
return POCs;
Replacement code
var sql = string.Empty;
if (IsAssociate == 0)
sql = string.Format(#"SELECT tblPOC.cntPOC,INITCAP(strLastName),INITCAP(strFirstName)
FROM tblPOC,tblParcelToPOC
WHERE tblParcelToPOC.cntPOC = tblPOC.cntPOC
AND tblParcelToPOC.cntAsOf = 0
AND tblParcelToPOC.cntParcel = {0}
ORDER BY INITCAP(strLastName)",
cntParcel);
else
sql = string.Format(#"SELECT cntPOC,INITCAP(strLastName), INITCAP(strFirstName)
FROM tblPOC
WHERE tblPOC.cntPOC NOT IN (SELECT cntPOC
FROM tblParcelToPOC
WHERE cntParcel = {0}
AND cntAsOf = 0)
AND tblPOC.ysnActive = 1
ORDER BY INITCAP(strLastName)",
cntParcel);
return Context.Database.SqlQuery<TBLPOC>(sql, "0").ToList<TBLPOC>();
The issue I'm having right now is when the replacement code is executed, I get the following error:
The data reader is incompatible with the specified 'TBLPOC'. A member of the type 'CNTPOCORGANIZATION', does not have a corresponding column in the data reader with the same name.
The field cntPOCOrganization does exist within tblPOC, as well as within the TBLPOC Entity. cntPOCOrganization is a nullable decimal (don't ask why decimal, I myself don't get why the previous contractors used decimals versus ints for identifiers...). However, in the past code and the newer code, there is no need to fill that field. I'm confused on why it is errors out on that particular field.
If anyone has any insight, I would truly appreciate it. Thanks.
EDIT: So after thinking on it a bit more and doing some research, I think I know what the issue is. In the Entity Model for TBLPOC, the cntPOCOrganization field is null, however, there is an object tied to this Entity Model called TBLPOCORGANIZATION. I'm pondering if it's trying to fill it. It too has cntPOCOrganization within itself and I'm guessing that maybe it is trying to fill itself and is what is causing the issue.
That maybe possibly why the previous contractor wrote the Oracle Command versus run it through the Entity Framework. I'm going to revert back for time being (on a deadline and really don't want to play too long with it). Thanks!

This error is issued when your EF entity model does not match the query result. If you post your entity model you are trying to fetch this in, the SQL can be fixed. In general you need to use:
sql = string.Format(#"SELECT tblPOC.cntPOC AS <your_EF_model_property_name_here>,INITCAP(strLastName) AS <your_EF_model_property_name_here>,INITCAP(strFirstName) AS <your_EF_model_property_name_here>
FROM tblPOC,tblParcelToPOC
WHERE tblParcelToPOC.cntPOC = tblPOC.cntPOC
AND tblParcelToPOC.cntAsOf = 0
AND tblParcelToPOC.cntParcel = {0}
ORDER BY INITCAP(strLastName)",
cntParcel);

Can Entity Framework Core run non-query calls?

Unfortunately my EF application has to call stored procedures I am unable to change. While this is not ideal I can normally get around it. However, I have a stored proc that does return anything. How does EF core deal with this? I know in previous versions you could run ExecuteNonQuery but I haven't been able to find anything similar in EF Core.
I normally run my queries through a helper as such, where T is a class that maps to a return type EF can serialize to:
context.Set<T>()
.AsNoTracking()
.FromSql(query, args)
.ToListAsync();
However it looks like Set always requires a type as does .Query. Nothing else I've seen off of context would allow you to make a non-queryable call. Am I missing something?
I am using Microsoft.EntityFrameworkCore: 1.2.0

You can use the DbContext.DatabaseExecuteSqlCommand method
using(var context = new SampleContext())
{
var commandText = "INSERT Categories (CategoryName) VALUES (#CategoryName)";
var name = new SqlParameter("#CategoryName", "Test");
context.Database.ExecuteSqlCommand(commandText, name);
}
Or you can revert to ADO.NET calls off the Context:
using (var context = new SampleContext())
using (var command = context.Database.GetDbConnection().CreateCommand())
{
command.CommandText = "DELETE From Table1";
context.Database.OpenConnection();
command.ExecuteNonQuery();
}

Backup SQL Server Schema With Data

I've been tasked with creating a backup of the data in our "default schema" database dbo to the same database using a new schema called dbobackup.
I honestly do not understand what this means as far as a database goes. Apparently, it is like having a database backup inside the existing database. I guess there is some advantage to doing that.
Anyway, I can't seem to find anywhere online that will allow me to do this.
I have found a few posts on here about copying the schema without data, but I need the data too.
Backup SQL Schema Only?
How do I check to see if a schema exists, delete it if it does, and then create a schema that accepts data in the current database?
Once I have the new schema created, can I dump data in there with a simple command like this?
SELECT * INTO [dbobackup].Table1 FROM [dbo].Table1;
That line only backs up one table, though. If I need to do this to 245 tables for this particular customer, I'd need a script.
We have several customers, too, and their databases are not structured identically.
Could I do something along these lines?
I was thinking about creating a small console program to walk through the tables.
How would I modify something like the code below to do what I want?
public static void Backup(string sqlConnection)
{
using (var conn = new SqlConnection(sqlConnection))
{
conn.Open();
var tables = new List<String>();
var sqlSelectTables = "SELECT TableName FROM [dbo];";
using (var cmd = new SqlCommand(sqlSelectTables, conn))
{
using (var r = cmd.ExecuteReader())
{
while (r.Read())
{
var item = String.Format("{0}", r["TableName"]).Trim();
tables.Add(item);
}
}
}
var fmtSelectInto = "SELECT * INTO [dbobackup].{0} FROM [dbo].{0}; ";
using (var cmd = new SqlCommand(null, conn))
{
foreach (var item in tables)
{
cmd.CommandText = String.Format(fmtSelectInto, item);
cmd.ExecuteNonQuery();
}
}
}
}

SQL Server already has this built in. If you open SQL Server Management Studio and right click on the database you want to back up, then select all tasks then backup, you will get an option to back up your database into an existing database.
This is the important part and why you should use the built in functionality: You must copy the data from one DB to the other DB in the correct order or you'll get foreign key errors all over the place. If you have a lot of data tables with a lot of relationships, this will really be hard to nail down on your own. You could write code to make a complete graph of all of the dependencies and then figure out what order to copy the table data (which is essentially what SQL Server already does).
Additionally, there are third-party programs available to do this type of backup as well (see: Google).

This is sort of a "work in progress" approach I got started with that looks promising:
public static void CopyTable(
string databaseName, // i.e. Northwind
string tableName, // i.e. Employees
string schema1, // i.e. dbo
string schema2, // i.e. dboarchive
SqlConnection sqlConn)
{
var conn = new Microsoft.SqlServer.Management.Common.ServerConnection(sqlConn);
var server = new Microsoft.SqlServer.Management.Smo.Server(conn);
var db = new Microsoft.SqlServer.Management.Smo.Database(server, databaseName);
db.Tables.Refresh();
for (var itemId = 0; itemId < db.Tables.Count; itemId++)
{
var table = db.Tables.ItemById(itemId);
if (table.Name == tableName)
{
table.Schema = String.Format("{0}", DatabaseSchema.dboarchive);
table.Create();
}
}
}
The only issue I am currently running into is that my db variable always comes back with Tables.Count == 0.
If I get a chance to fix this, I will update.
For now, I've been told to remove this piece of code and check my code in.

How can you connect to a ProgressDB data provider with Dapper?

Please read the comments of the answer for a more complete understanding of what the problem is/was
First, I read through a lot of the other SO questions related to this and still can't get this to work with a basic setup. Here is the related question I have already read:
Passing query parameters in Dapper using OleDb
EDIT: The troubleshooting below is somewhat misleading. The only thing that was going wrong was the query syntax from the Github example was not valid using the ProgressDB OpenEdge driver.
The problem with that question's answer and with the example given in the documented Git examples is that a true ODBC object is not being used, but rather an OleDbConnection object. This causes problems with the scenario where I am trying to use Dapper. Some background and restrictions to my scenario:
I cannot change the DB technology, we are connecting to an Progress DB. The connection string to connect to the DB: connectionString="PROVIDER=MSDASQL;DRIVER={Progress OpenEdge 10.2A Driver};HOST=...;PORT=...;DB=mfgsys;UID=...;PWD=...;DIL=READ UNCOMMITTED" Notice the Provider: MSDASQL
According to MSDN, https://msdn.microsoft.com/en-us/library/a6cd7c08%28v=vs.110%29.aspx - "The .NET Framework Data Provider for OLE DB does not work with the OLE DB provider for ODBC (MSDASQL). To access an ODBC data source using ADO.NET, use the .NET Framework Data Provider for ODBC."
When I attempt to use the OdbcConnection object with Dapper I get the following error: "System.Data.Odbc.OdbcException : ERROR [HY000] [DataDirect][ODBC Progress OpenEdge Wire Protocol driver][OPENEDGE]Syntax error in SQL statement at or about "= ?, Age = ?" (10713)"
I am using the exact same query syntax as the other SO question:
var row = _odbcConn.Query("select Id = ?, Age = ?", new DynamicParameters(new{foo = 12, bar = 23}) {RemoveUnused = false}).Single();
I also removed the DynamicParameters object and attempted with a dynamic object with same result:
var row = _odbcConn.Query("select Id = ?, Age = ?", new{foo = 12, bar = 23}).Single();
Is there a way to accomplish this simple query using an OdbcConnection object? Or does this really have more to do with the specific Progress driver we are using and as such precludes using Dapper?
Edit
Including working ADO.Net code per requests below, the Build.FromReader<EmployeeDataModel>(reader) just loops through the reader and maps the columns with hard coding and is confirmed to work:
public class EmployeeRepository : IEmployeeRepository
{
private readonly OdbcConnection _sqlConn = new OdbcConnection();
public EmployeeRepository() : this(ConfigurationManager.ConnectionStrings["TCI_Epicor"].ConnectionString) { }
public EmployeeRepository(string connString)
{
_sqlConn.ConnectionString = connString;
}
public EmployeeDataModel GetById(string id)
{
try
{
_sqlConn.Open();
using (OdbcCommand command = new OdbcCommand())
{
command.Connection = _sqlConn;
command.CommandType = CommandType.Text;
command.CommandText = GetEmployeeDataQuery();
command.Parameters.Add("empID", OdbcType.NVarChar);
command.Parameters["empID"].Value = id;
var reader = command.ExecuteReader();
return Build.FromReader<EmployeeDataModel>(reader);
}
}
catch
{
return new EmployeeDataModel();
}
finally
{
_sqlConn.Close();
}
}
private string GetEmployeeDataQuery()
{
var sb = new StringBuilder();
sb.AppendLine("SELECT EmpID as 'EmployeeID',");
sb.AppendLine(" FirstName + ' ' + LastName as 'EmployeeName'");
sb.AppendLine(" FROM MFGSYS.PUB.EmpBasic");
sb.AppendLine(" WHERE EmpID = ?");
return sb.ToString();
}
}

If the problem is using anonymous (?) parameters, then:
var row = _odbcConn.Query(
"select Id = ?foo?, Age = ?bar?", new { foo = 12, bar = 23 }
).Single();
Dapper will rewrite that as per your original query, but will know which parameter to put where.
However, if the problem is that the ODBC provider does not support parameters: I can't help much with that :( If you can show how to do it in working ADO.NET code, I can probably show you how to do it easier via dapper.

ODAC seems to be caching table schema?

I'm using Oracle's ODAC.NET for a .NET 3.5 project against an Oracle 11 Express database, and I'm seeing behavior that I can't explain (and can't seem to work around).
ODAC should be the latest, I just pulled it 3 days ago, but the versions are as follows:
Oracle.DataAccess.dll version 2.112.3.0 (release 5)
oci.dll (instant client) version 11.2.0.1
I have a Table, People, that has 3 columns:
ID
FirstName
LastName
In code I run an ALTER TABLE command, using OracleCommand.ExecuteNonQuery, to add a new column named "MIDDLE_NAME" to the table. That command succeeds. If I look at the table with Oracle SQL Developer, the columns shows up. All well and good.
Now if I run use OracleCommand.ExecuteReader with a command text of SELECT * FROM People right after I do the alter table, I get back data with only 3 columns, not 4!
Here is code that reproduces the problem:
public void FieldTest()
{
var sql1 = "CREATE TABLE People (" +
"ID NUMBER PRIMARY KEY, " +
"FirstName NVARCHAR2 (200), " +
"LastName NVARCHAR2 (200) NOT NULL)";
var sql2 = "ALTER TABLE People " +
"ADD Middle_Name NUMBER";
var sql3 = "SELECT * FROM People";
var sql4 = "SELECT column_name FROM all_tab_cols WHERE table_name = 'PEOPLE'";
var cnInfo = new OracleConnectionInfo("192.168.10.246", 1521, "XE", "system", "password");
var connectionString = BuildConnectionString(cnInfo);
using (var connection = new OracleConnection(connectionString))
{
connection.Open();
using (var create = new OracleCommand(sql1, connection))
{
create.ExecuteNonQuery();
}
using (var get = new OracleCommand(sql3, connection))
{
using (var reader = get.ExecuteReader())
{
Debug.WriteLine("Columns: " + reader.FieldCount);
// outputs 3, which is right
}
}
using (var alter = new OracleCommand(sql2, connection))
{
alter.ExecuteNonQuery();
}
using (var get = new OracleCommand(sql3, connection))
{
using (var reader = get.ExecuteReader())
{
Debug.WriteLine("Columns: " + reader.FieldCount);
// outputs 3, which is *wrong* <---- Here's the problem
}
}
using (var cols = new OracleCommand(sql4, connection))
{
using (var reader = cols.ExecuteReader())
{
int count = 0;
while (reader.Read())
{
count++;
Debug.WriteLine("Col: " + reader.GetString(0));
}
Debug.WriteLine("Columns: " + count.ToString());
// outputs 4, which is right
}
}
}
}
I've tried some things to prevent the behavior, and none of them give me back the 4th column:
I close the connection and re-open it
I use a new OracleConnection for the SELECT than for the ALTER
I use the same OracleConnection for the SELECT and for the ALTER
I use a new OracleCommand for the SELECT than for the ALTER
I use the same OracleCommand for the SELECT and for the ALTER
I call PurgeStatementCache on the connection between the ALTER and SELECT
I call FlushCache on the connection between the ALTER and SELECT
I explicitly Close and Dispose the OracleCommand and OracleConnection (as opposed to the using block) used for the ALTER and SELECT
Restarted the calling PC and the PC hosting the Oracle database.
If I look at the column list by doing a SELECT * FROM all_tab_cols, the new column is there.
The only thing that seems to work reliably is closing the app and re-starting it (well it's from a unit test, but it's a shutdown and restart of the test host). Then I get that 4th column. Sometimes I can use breakpoints and re-execute queries and the 4th column will appear, but nothing that is specifically repeatable with straight execution of code (meaning without setting a break point and moving the execution point back up).
Something in the bowels of ODAC seems to be caching the schema of that table, but I can figure out what, why or how to prevent it. Anyone have any experience with this, or ideas how I might prevent it?

I know this answer comes years later but if new readers run into problems with caching try setting:
Metadata Pooling = false, Self Tuning = False and Statement Cache Size = 0
...in the connection string. Keep in mind that there are performance implications for doing so.
https://docs.oracle.com/database/122/ODPNT/featConnecting.htm#GUID-0CFEB161-68EF-4BC2-8943-3BDFFB878602

Maybe post some of your C# code. The following is a test that behaves as expected, meaning I can see the new column immediately after adding it. This is using odp 11.2 rel 5 hitting an 11g db, using 4.0 framework:
The test table is:
CREATE TABLE T1
(
DTE DATE default sysdate
);
Drop and recreate it after each run of the following C# code (a bit dirty but anyway):
string connStr = "User Id=xxx;Password=yyy;Data Source=my11gDb;";
using (OracleConnection con = new OracleConnection(connStr))
{
string s = "ALTER TABLE T1 ADD (added_col VARCHAR2(10))";
using (OracleCommand cmd = new OracleCommand(s, con))
{
con.Open();
cmd.ExecuteNonQuery();
string s2 = "select column_name from all_tab_columns where table_name = 'T1'";
//con.FlushCache(); // doesn't seem to matter, works with or without
using (OracleCommand cmd2 = new OracleCommand(s2, con))
{
OracleDataReader rdr = cmd2.ExecuteReader();
for (int i = 0; rdr.Read(); i++)
{
Console.WriteLine("Column {0} => {1}",i+1,rdr.GetString(0));
}
rdr.Close();
}
}
}
Output:
Column 1 => DTE
Column 2 => ADDED_COL
Edit:
Ah, ok, I see what you're saying, it looks like statement caching. I played around with changing the cache size to 0 (in conn string, use "Statement Cache Size=0"), and also tried cmd.AddToStatementCache = false, but these did not work.
One thing that does work is to use a slightly different string, like adding a space. I know its a hack, but this is all I can get to work for me anyway.
Try your example with:
var sql3 = "SELECT * FROM People";
var sql5 = "SELECT * FROM People "; // note extra space
And use sql3 before adding column, and sql5 after adding a column.
Hope that helps